I always measure my quilts through the center, up and down and side to side, I find this works really well and I never have to square them up. They are the same size on both sides and the ends. I put 5 pins in both quilt and border strip, when I sew I pinch both edges in between the pins, sew to that point and then sew to the pin. I do this until the border is sewn on. This may take a few extra minutes but, I figure I have so much time in making a quilt that a few more minutes won't hurt. I am my worse critic and try to please myself. I only make quilts for my own entertainment, although I have given many away. I always make sure I'm pleased with my work. Make yours however it works. Others know what they are talking about.